Method for producing a multilayer printed-circuit board

Abstract

A method for producing a multilayer printed-circuit board is disclosed, the method substantially comprises the steps of: printing an electrically conductive paste on one or both sides of a predetermined number of electrically insulated prepreg base plates to form thereon electrically conductive circuits; drying the circuit processed base plates; laminating and pressing the circuit processed base plates into a single laminated board; making holes in the single laminated board, the holes being extended through in the direction of the thickness of the board; and applying an electrical conductor to the inner faces of the holes to make electrically conductive the laminated circuits to each other within the single laminated board.

What is claimed is: 
     
       1. A method for producing a multilayer printed-circuit board using an electrically conductive copper paste including 70-85% by weight of copper powder, 15-30% by weight of at least one resin selected from the group of phenol resin, epoxy resin, polyestel resin and xylene resin, and a specific additive selected from anthracene and the derivative thereof, the method comprising the steps of: Printing the electrically conductive copper paste in a desired circuit pattern on at least one side of each of a predetermined number of electrically insulated prepreg base plates of epoxy resin;   drying the base plates by heating the base plates at approximately 80° C. for approximately 30 minutes to harden the base plates and the copper paste;   laminating the base plates by pressing the base plates together and heating the base plates at approximately 170° C. for approximately 30-60 minutes to additionally harden and fixedly attach the base plates to each other and thereby form a single multilayer printed-circuit board; and   electrically connecting the multilayer printed circuits of the multilayer printed-circuit board.   
     
     
       2. A method for producing a multilayer printed-circuit board using an electrically conductive copper paste including 70-85% by weight of copper powder, 15-30% by weight of at least one resin selected from the group of phenol resin, epoxy resin, polyestel resin and xylene resin, and a specific additive selected from anthracene and the derivative thereof, the method comprising the steps of: printing the electrically conductive copper paste in a desired circuit pattern on at least one side of each of a predetermined number of electrically insulated prepreg base plates of epoxy resin;   drying the base plates at a first predetermined temperature for a first predetermined period of time to harden the base plates;   laminating the base plates and pressing the base plates at a second predetermined temperature a second predetermined period of time to additionally harden and laminate the base plates into a single multilayer printed-circuit board;   forming holes to extend through the single multilayer printed-circuit board in the direction of the thickness from the top to the bottom thereof;   masking all surfaces of the board with a resist except for the surfaces of the holes through the board;   processing the inner surfaces of the holes with an electrically conductive element to electrically connect the multilayer printed circuits of the board;   removing the resist from the single multilayer printed-circuit board; and   coating all surfaces of the single multilayer printed-circuit board with a flux;   said first predetermined temperature being approximately 80° C., said second predetermined temperature being approximately 170° C., said first predetermined period of time being approximately 30 minutes and said second predetermined period of time being approximately 30-60 minutes.